Drafting device



1 June 28 [1927.

i J. o. FORTIN DRAF-TING DEVICE Filed 0ct.2, 1922 2 Sheets-Sheet 1 m l/e060)".-

June p J. O. FORTIN DRAFTING DEVICE Filed Oct. 2. 1922 2 Sheetg-Sheet 2 w w @E of the invention as it appears Patented June 28, 1927.

UN! TED S TA TES V 1,6331528 PATENT OFFICE.

JOSEPH O. :FORTIN, OF ,OTTAWAQONTA'BIO, CANADA.

DRAVFTING DEVICE.

Application filed October 2, 1922, Serial No. 591,850, and inflanada oc'c ber 4, 1921.

This invention relates to drafting machines and 'more particularly to machines of the class comprising'a plurality-of pivotally connected -parallelogram-shaped structures, one of Whichhas one of its short-links connected to an anchoring device While one short link of another structure carries a drafting appliance such as one or more, rules or a protractor.

It is the object ofthe present'inventionto bodiments of the invention by Way of eX- Figure Figure 2 is a planvieW of one form of drafting appliance,

Figur'eB'isa plan .vieW of another form of drafting appliance,

' Figure 4 is a sectional elevation on line 4 41, Figure 3,

Figure 5 is a fragmentary sectionaleleva- .:tion through the three pivotal points of the parallelogram structures on the ,linev5 5 of Figure l, i

Figure 6 .is a sectional elevationsimilar to Figured approximately on line 4-4 of Figure3-but showinga modified means for connecting the drafting appliance,

Figure 7 is a fragmentary sectionalzelevationapproximately on line 5-5 ofFigure 1 but illustrating modified clampingmeans for thepivotalpoints of the parallelogram struc- =tures,

I Figure 9 is a plan view showin one [form for storage a or transport The anchoring device may comprise a bar 1 which a is secured as by means. of screws 2 to atableor drawing board. Secured tothe bar 1 .is a truncated. cone member 3 which is adapted (to engage aconi'cal recess in ameni- ,ber 4. :A .scre wfi passes freely throughholes in a ishortilink. 6of one. or the parallelogram structures and "also through 'holes in the .co-

lis a plan view of the invention,

Figure 8 is .a partial sectional elevation on line 8-8 of :Figure2, and

operating cone'n'lembers and 1V andengages a'tapped hole lnth'e bar 1. The link'6' is rigidly connected to the member 4.

Thelonger parallel-links 8 of'the first par- "allelogram structure are pivoted'to the ends of 'link6 and to the other short link 9 by means of pins 7 The short link 9 may be supported at the same level as link 6 by ineans such as inverted cone shaped feet'l O. The ;l1nk9 is secured to a truncated cone 8 engaging a conical recess in a member a which is secured to a short link'll of the second parallelogramstructure. A screw 5 passes freely through holes in link 11, membersat andl and is screwed into link9f The longer links 12 of'the second parallelogram structure are pivotally attached .to link 11' and the other short link '13 of the second parallelogram structure bymea-ns of pins 7.

The bars or links '8 and 12 are preferably provided with a series of holes spaced at.

equal distances apart to receive'the pins .7 for the purpose of altering the distance'between the'parallel links 6 and'9 and ,betWeen the links 11 and 13. The links 8 and '12 can at all times swing upon their pivots '7. The linksare initially adjusted to suit the position andfsize of the surface to be drawn upon, for example, as shown in Figure 1. The screws5 are'then screwed down to clamp link 6 in respecttogbar 1 and link-9 inrespect to link 11. The link '13 Will then remainin the same angular position With respect to link 6 'Whateverthe relative angular position be held ,stationaryand the closed parallelo- Vgram structure may be unclamped, opened up and}reclamped, and then the movement of the drafting membermay be continued and it Will maintain its original angular po- SltiOHWltll regard to the Work.

Secured .to the underside of linlrlEl is a member .4: having a conical recess adapted to ;.*e.c -e v;e a .rtruncated com 18 secured to a ;graclnated plate or r ng 19 by means of 'SCIBWS,21;QH i11dkeygd tQB. bushing vl5 as at- 22. -Benea.th {the plate 19 is provided afba'r'l? vclamped .in vany suitablermann'er' to thelplate 19., for example, by a clamping screw -26 passing through an arcnate-rslot in the plate 19 and screwed into bar 17. The bar 17 and parts carried thereby are supported as by means of three feet 24, two of which, as shown in Figures 4, 5 and 6, are carried by rods 23 secured to bar 17 and locked in ad justed position by screws 25.

Avernier scale on an are shaped plate 27 is arranged to cooperate with the graduations on plate 19, the plate 27 being secured to the bar 17 by means of a screw 28. The plates 19 and 27 are marked respectively with aliquot and integral graduations. For surveyors and those who want to read to one minute of arc, the plate 19 is graduated to even degrees and is indexed O to 180 and 180 to 360 and from 180 backwards to 90, as shown in Figs. 1 and 3. Vernier-s reading to one minute are graduated through 120 divisions of 59 minutes each, 60 to right and 60 to left of an index zero. In this case the graduated ring must have 60 unindeXed graduations to the right of 180 as shown in Fig. 3, for allowing a reading of 179 59. For those who want a Vernier of minutes, four graduations of 45 minutes each on either side of the zero index, will constitute the length of the Vernier, in this case the integral graduations will be carried four marks beyond 180. And for those who require even degrees only, an ordinary marker will do.

As shown in Figure 3 two rules are secured to the end of bar 17. The rules, one in line with bar 17 and one at right angles thereto, are illustrated as being secured to bar 17 by means of rods 29 screwed into tapped holes in rod 17. The rods 29 rest in semi-cylindrical grooves in metal plates 31 and are secured therein by screws 30, the plates 31 being secured to the rule by screws 32. The holes in the rule through which the screws 32 pass may be of larger diameter than the screws so that the rules may be ad justed about their longitudinal axes to ensure that the ruling edge is flat against the drawing surface.

Figure 6 illustrates a modified means of pivotally attaching and clamping the plate 19 to the bar 17. A flange on a bolt 36 holds the plate 19 against the bar 17, the head of bolt being accommodated in a recess in a truncated cone member 34 which is attached to the plate 19, by screws 21. The link 13 of the second parallelogram structure carries a conically recessedmember 1 which is adapted to be clamped in engagement with cone 3% by means of a bolt 33. In small machines the plate 19 need not be complete 1y circular and in such cases the clamping screw 26 may be located in an arcuate slot on the graduated side of the plate 19. In Figure 6 the bar 17 extends further than in Figure 4 and carries one of the rules which is attached by means of a screw which passes through bar 17. v

In Figure 7 is shown a further form of machine which is simpler, lighter and cheaper. In this modification the female cone pieces 1 are eliminated but their functions are fulfilled by conical recesses in the links 6, 11 and 13.

Figures 2 and 8 are respectively plan and partial section of an attachment'suitable for use by a surveyor. In this form a plate 38 is pivotally attached to link 13 by means of co-acting cone members 4 and 37 which may be clamped by a screw 5, the plate 38 being secured to cone 37 by screws 39. The plate 38 is approxin'iately triangular and a graduated ring 40 is attached to it by means of screws 11. The ring 4:0 is supported in horizontal position as by means of feet 42. A flange on an annular graduated plate 43 lies in a recess in the inside of plate 40 and may be clamped to plate 4-0 by means'of a nut and bolt 14, the bolt having a flange engaging the underside of ring 10 and keyed to ring 13 by a pin 15. Two elbows 16 are carried by the ring 4L3 and a graduated rule i8 is attached to the elbows by means of screws 47, engaging slots in the brackets which permits adjustment of the rule.

It will be understood that various changes may be made in the details of the construction and in the drafting attachments without departing from the scope of the invention as defined in the appended claims. For example, any number of parallelogram structures may be connected together as may be necessary to move the drafting attachment to the position where the drawing work is to be done.

hat I claim is 1. A drafting machine comprising a plir rality of pivotally connected parallelogramshaped structures, each consisting of a pair of parallel short links pivotally connected by a pair of parallel longer links, an anchoring device, a single vertical pivot member on said anchoring device, means on said pivot member for clamping the short link at one end of the machine in any desired angularposition to said device, a drafting member rotatable about the middle point of the short link adjacent the other end of the machine, and a vertical pivot member for connecting the other short link of each parallelogram structure to the adjacent short link of the other parallelogram structure.

2. A drafting machine comprising a plurality of pivotally connected parallelogramshaped structures, each consisting of a pair of parallel short links pivotally connected by a pair of parallel longer links, an anchoring device, a single vertical pivot member on said anchoring device, means on said pivot member for clamping the short link at one end of the machine in any desired position to said device, a single vertical pivot member arranged at the middle point of the short link adjacent the other end of the machine, a drafting member, means for clamping said drafting member on said last mentioned pivot in any desired angular position in relation to the adj acentshort link, a vertical pivot member for connecting the other short link of each parallelogram structure to a short link of the adjacent parallelogram structure and means on said last named pivot member for clamping said pivotally connected short links to each other in any desired angular position in relation to each other.

3. A drafting machine as claimed in claim 1, comprising also a bar pivotally mounted on the short link nearest the drafting memher, a graduated plate mounted on the pivot of said bar between the bar and the link, index means carried by the bar and cooperating with the graduations on said plate,

means for clamping the link to the plat-e and means for clamping the plate to the bar.

4. A drafting machine as claimed in claim 1, comprising also a bar pivotally mounted on the link nearest the drafting member, means for attaching a rule to said bar adjustably about the longitudinal axis of the rule.

5. A drafting machine as claimed in claim 30 1, comprising also a bar pivotally mounted on the link nearest the drafting member,

cylindrical rods carried by said bar at right angles to each other, a rule for each rod, brackets on said rules having semi-circular recesses to receive the rods and clamping screws adapted to pass through holes in the rods and engage tapped holes in the rules, the holes in the rods being of larger diameter than the screws.

6. A drafting machine comprising an anchoring device, a pair of parallelogramshaped structures each comprising four pivotally connected bars, a drafting member, a single vertical pivot member connecting the anchoring device to an end bar of one of said structures, a single vertical pivot member connecting said drafting member to an end bar of the other of said structures, a single vertical pivot member connecting the remaining two end bars of said structures and clamping means associated with each of said pivot members for clamping together the said parts which are connected by said pivot members, so that said drafting member may be angularly adjusted Without movement of said structures, or either of said structures may be opened or closed independently of each other and of the anchoringdevice and drafting member.v

J. O. FORTIN. 

